ARPANET’s coming out party: when the Internet first took center stage

Forty years ago the founders of the Internet had a revelation.

It was mid-1971. Ten scientists met at Massachusetts Institute of Technology's Tech Square in Cambridge. They had been given a task by the director of the Pentagon's Information Processing Techniques Office. The moment had arrived, Larry Roberts told the group's leaders, to publicly demonstrate IPTO's crowning achievement: the Advanced Research Projects Agency Network, forerunner of the Internet.

The ARPA Network, "was virtually unknown everywhere but the inner sancta of the computer research community," write Internet historians Katie Hafner and Matthew Lyon in their engaging book Where Wizards Stay Up Late. "Roberts knew it was time for a public demonstration."

The campaign went into high gear 40 years ago. President Nixon had nominated Lewis F. Powell and William H. Rehnquist to the Supreme Court. The United Nations General Assembly voted to expel Taiwan and admit the People's Republic of China. The rock opera Jesus Christ Superstar premiered on Broadway. Millions of Americans focused on these events had no sense of the significance of the ARPANET project.

But soon a critical mass of scientists and engineers would realize its importance. The demo took a year to plan. It was held at the first International Conference on Computer Communication in Washington, DC in October of 1972. And it accomplished what its organizers hoped. "Many skeptics were converted by witnessing the responsiveness and robustness of the system," remembers Internet pioneer Vint Cerf. Out of that "pivotal" meeting came a new research group dedicated to furthering the cause of distributed packet switching.

Not only was the first ARPANET exhibition a crucial moment in the development of the 'Net, but, by all accounts, it was lots of fun. And so, via Hafner and Lyon's narrative, we retell the story here.

Making it real

Through 1971 the ARPANET expanded from its four original "nodes" located at UCLA, the Stanford Research Institute, UC Santa Barbara, and the University of Utah to fifteen nodes. The computers that managed the packet switching and routing between these hosts and the network were called Interface Message Processors (IMPs), built by the engineering firm Bolt Beranek and Newman. By September of 1971, a Terminal IMP (TIP) had been installed, which permitted direct terminal access to the network. One of the Internet's earliest protocols, Telnet, facilitated peering into the doings of the ARPANET and performing various tasks.

An early e-mail protocol had also been developed, and file transfer applications were coming, but "it was TIPs and Telnet together that paved the way for rapid expansion of the network," Hafner and Lyon explain. One member of the MIT group suggested a video taped presentation of the demonstration. Al Vezza of MIT's project MAC strongly objected to this idea. The show had to be live. It had to be real time. "It had to be something that could be touched and controlled by anyone just sitting down at a terminal."

But a live event represented a huge gamble. The ARPANET's creators had relatively little hands-on experience with Telnet and file transfer apps. The ICCC demo could conceivably flop, but if it worked, "it would prove the network was not only real but useful."

For almost a year Bob Kahn of BBN and Vezza traveled the country looking for computer industry vendors who could bring equipment that the TIP could link to the ARPANET. The idea was simple. Conference goers and the general public would sit down at the machines, log on, and access the network. They would do things with remote applications. They would find files on distant computers and print them out. Then they would understand.

Crazy turtle

As a veritable army of vendors, graduate students, and ARPA folk began actually putting together the logistics of the demo, "a certain panic" set in. In fact, Roberts and Kahn had hoped for this. They saw the conference as a deadline that would drive the network to perfect itself. The show was set up "to force the utility of the network to occur to the end users," Bob Kahn later explained.

By early October of '72, everyone was scrambling like mad. The big moment was Monday morning, October 24 at the DC Hilton. The event would last for two-and-a-half days. "If somebody had dropped a bomb on the Washington Hilton, it would have destroyed almost all of the networking community in the U.S. at that point," Kahn recalled. But by the Saturday before the conference opened, Bolt Beranek's TIP "was like a king on a throne of wire running to all corners of the room."

The team spent Sunday struggling with glitches. Networking pioneer John Postel sat in the exhibition area, linked to the UCLA ARPANET host. He'd put together a demonstration allowing users to retrieve a file in Boston through a UCLA host computer, then print it out at the Hilton.

But when Postel gave his demo a try, the printer next to him sat still:

He looked around the room. There were a lot of other demonstrations, one of which was a small robotic turtle built at MIT. The turtle was built to demonstrate how a computer program could be written to direct the motion of a machine. Kids could write their own programs in the LOGO language that said 'go left, go right, go forward, back up, move sideways,' and when the program was run, the turtle would do that. At the moment, however, the turtle was jumping up and down, twitching and jerking crazily. Instead of sending Postel's file to the printer, the system had accidentally sent it to the turtle port.

Around Postel and his turtle other vendors and developers set up their applications: chess games, geography quizzes, an Associated Press news wire reader, and an air traffic control simulator. Everybody went home and got ready for the big moment.

I've killed it

Monday morning October 24 arrived. Conference attendees meandered into the exhibition. One sat down at a computer, followed some instructions, and tried to access a computer that most likely wasn't operational at the moment.

"HOST DEAD," came the line response.

"Oh, my God. I've killed it!" he cried out in a panic.

Another two attendees sat down at machines and had an experience that would be shared by millions of cell phone texters three decades later. They both logged into the University of Utah host and accessed the TALK protocol.

"Where are you?" one typed.

"I'm in Washington," the other replied.

"Where?"

"At the Hilton."

"Well, I'm at the Hilton too."

They were, of course, practically sitting next to each other.

Perhaps the most famous applications demonstrated at the ARPANET event were two line-entry chatterbot programs: PARRY and ELIZA—the latter also known as The Doctor. Stanford psychiatrist Kenneth Colby wrote PARRY in 1972—a response program that simulated a paranoid psychotic. MIT's Joseph Weizenbaum created The Doctor in the mid-1960s. It mimicked the studiously patient questions of a Rogerian psychiatrist.

A month before the exhibit, UCLA set up a dialogue between The Doctor and PARRY. Some of it went like this:

"Good Evening. Tell me your problems," The Doctor began. "Please terminate input with a period or a question mark."

PARRY: *Gambling has been nothing but trouble to me.

The Doctor: Why do you say that just now?

*I've had experience with crooks gambling at the track.

I am not sure I understand you fully.

*I've already told you enough about that.

Oh? I enough about that?

*I went to the races.

Please go on.

*Do you know anything about bookies?

What makes you think I know anything about bookies?

*A bookie didn't pay me off once.

What does that suggest to you?

*I beat up the bookie who did not pay off, and I thought he might use his friends in the underworld to get even with me.

An enlightening moment

Over nearly three days, hundreds of people tried the apps, accessed the networks, and marveled at the ARPANET. Not all of them came with an open mind. Robert Metcalfe later described the results of his thankless job, giving a gaggle of AT&T Vice Presidents a tour of the exhibit. He demonstrated the system, and unintentionally confirmed an old and unfortunate near certainty. Whenever you try to show skeptics some new technology, that's the moment when it will fail:

"So I was demo'ing the system, and for the only time in that whole show, the TIP crashed," Metcalfe recalled. "The only time."

It went down for about ten or twenty seconds. It finally came back up again. We reestablished connection and it never went down again. But this was a very enlightening moment for me because when I looked up, you know, they were happy that it crashed. They made no point of hiding their joy. Because this confirmed for them that circuit switching was better and more reliable than packet switching, which was flaky and would never work. And I had been working on this for two or three years, and it really pissed me off.

Ironically, it was AT&T that provided a crucial data link for the show. But as Hafner and Lyon note, many others came away from the exhibit true believers. "The ICCC demonstration did more to establish the viability of packet-switching than anything else before it," their passage on the exhibit concludes. "As a result, the ARPANET community gained a much larger sense of itself, its technology, and the resources at its disposal."

From the meeting came a crucial alliance, the International Packet Network Working Group, which studied ways to connect packet switched networks as they emerged around the world. Now the Internet was really on its way.

"Here we could show it off," remembered Internet pioneer Leonard Kleinrock, "we knew it would work. Even if it fumbled, these things were fixable. It was a wonderfully exciting experience."

Further reading

Katie Hafter and Matthew Lyon, Where Wizards Stay Up Late: The Origins of the Internet (Simon and Schuster, 1996).

Matthew Lasar
Matt writes for Ars Technica about media/technology history, intellectual property, the FCC, or the Internet in general. He teaches United States history and politics at the University of California at Santa Cruz. Emailmatthew.lasar@arstechnica.com//Twitter@matthewlasar